MAGNETIC SENSOR FOR USE WITH HAND-HELD DEVICES

• US 20100161084A1
• Filed: 02/12/2010
• Published: 06/24/2010
• Est. Priority Date: 02/01/2006
• Status: Active Grant

• Current Assignee: Memsic Semiconductor (Wuxi) Co., Ltd. (MZ Investment Holdings Ltd.)
• Original Assignee: Memsic Incorporated (MZ Investment Holdings Ltd.)
• Inventors: Guozhi, Pan, Jianping, Yu, Zhao, Yang, Liu, Haidong
• Granted Patent: US 8,139,030 B2
• Time in Patent Office: Days
• US Class Current: 700/85
• CPC Class Codes: G01C 17/02 Magnetic compasses
• CPC Class Codes: G01C 17/28 Electromagnetic compasses with north seeking magnetic elements and having electric pick-offs G01C17/26
• CPC Class Codes: G01R 33/04 using the flux-gate principle
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 2200/1637 Sensing arrangement for detection of housing movement or orientation, e.g. for controlling scrolling or cursor movement on the display of an handheld computer
• CPC Class Codes: G06F 3/017 Gesture based interaction, e.g. based on a set of recognized hand gestures interaction based on gestures traced on a digitiser G06F3/04883
• CPC Class Codes: G06F 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors
• CPC Class Codes: H04M 1/2748 by matching character strings
• CPC Class Codes: H04M 1/6066 including a wireless connection
• CPC Class Codes: H04M 1/72403 with means for local support of applications that increase the functionality
• CPC Class Codes: H04M 1/72436 for text messaging, e.g. short messaging services [SMS] or e-mails
• CPC Class Codes: H04M 1/72469 for operating the device by selecting functions from two or more displayed items, e.g. menus or icons
• CPC Class Codes: H04M 2250/12 including a sensor for measuring a physical value, e.g. temperature or motion telephones including GPS signal receivers H04M2250/10

Abstract

The use of magnetic field sensing to perform sophisticated command control and data input into a portable device is disclosed. A magnetic field sensor is embedded or fixedly attached to a portable device to measure changes in the magnetic field strength and/or direction accompanying movement, motion or tilt of the device in one-, two- or three-dimensions when the portable device is used to air-write or make gestures.

Claims

1. A system for controlling a portable device using magnetic-field sensing, the system comprising:

a magnetic field-sensing device that is structured and arranged to sense changes in a magnetic field that accompany movement of the portable device;

a data acquisition unit that receives data signals transmitted from the magnetic field-sensing device;

memory for storing data that includes a plurality of pre-determined correlations between magnetic field changes resulting from movement of the portable device that are each uniquely associated with a discrete control operation; and

a control unit that analyzes signals from the data acquisition unit;

identifies characteristics of changes in a magnetic field that accompany movement of the portable device;

compares the characteristics of changes in a magnetic field with the plurality of pre-determined correlations; and

automatically executes the discrete control operation associated with the pre-determined correlations when the characteristics of changes in the magnetic field match the pre-determined correlations.

2. The system as recited in claim 1, wherein the magnetic-field sensing device is a magnetic compass or a magnetometer.

3. The system as recited in claim 1, wherein the magnetic field-sensing device is structured and arranged to detect changes in at least one of a magnetic field strength and a magnetic field direction.

4. A system for inputting data into a portable device using magnetic-field sensing, the system comprising:

a magnetic field-sensing device that is structured and arranged to sense changes in a magnetic field that accompany movement of the portable device;

a data acquisition unit that receives data signals transmitted from the magnetic field-sensing device;

memory for storing data that includes a plurality of pre-determined correlations between magnetic field changes resulting from movement of the portable device that are each uniquely associated with a discrete control operation; and

a control unit that analyzes signals from the data acquisition unit;

identifies characteristics of changes in a magnetic field that accompany motion or movement of the portable device;

compares the characteristics of changes in a magnetic field with the plurality of pre-determined correlations; and

automatically executes the discrete control operation associated with the pre-determined correlations when the characteristics of changes in the magnetic field match the pre-determined correlations.

5. The system as recited in claim 4, wherein the magnetic-field sensing device is a magnetic compass or a magnetometer.

6. The system as recited in claim 4, wherein the magnetic field-sensing device is structured and arranged to detect changes in at least one of a magnetic field strength and a magnetic field direction.

7. A method for controlling a portable device using changes in at least one of a magnetic field strength and a magnetic field direction that accompany movement of the portable device to perform control operations, the method comprising:

installing or embedding a magnetic-field sensing device in the portable device;

providing a plurality of pre-determined correlations between changes in magnetic field properties due to movements and discrete control operations;

detecting changes in magnetic field properties due to movements of the portable device with the magnetic-field sensing device;

comparing the changes in magnetic field properties due to movements with the plurality of pre-determined correlations; and

initiating the discrete control operation that is associated with the corresponding correlation so detected.

8. The method as recited in claim 7, wherein detecting change in magnetic field properties includes detecting at least one of changes in magnetic field strength and changes in magnetic field direction.

9. A method for inputting data into a portable device using movement of the portable device to perform control operations, the method comprising:

installing or embedding a magnetic-field sensing device in the portable device;

providing a plurality of pre-determined correlations between changes in magnetic field properties due to movements and discrete control operations;

detecting changes in magnetic field properties due to movements of the portable device with the magnetic-field sensing device;

comparing the changes in magnetic field properties due to movements with the plurality of pre-determined correlations; and

initiating the discrete input operation that is associated with the corresponding correlation so detected.

10. The method as recited in claim 9, wherein detecting change in magnetic field properties includes detecting at least one of changes in magnetic field strength and changes in magnetic field direction.